NVS-PAK1-1 is a potent allosteric inhibitor of PAK1 with an IC 50 of 5 nM for dephosphorylated PAK1 and 6 nM for phosphorylated PAK1 as assessed. Inhibition is ATP-competitive, most likely due to indirect competition due to incompatibility of ATP binding with the DFG-out binding conformation of the allosteric compound. NVS-PAK1-1 has an IC50 of 270 nM against dephosphorylated PAK2 and 720 nM against phosphorylated PAK2 respectively [1].

PAK2:0.4 μM (Kd), PAK1:5 nM, PAK1:0.007 μM (Kd), PAK2:270 nM

NVS-PAK1-1 potently inhibits PAK1 (S144) autophosphorylation at 0.25 μM in the Su86.86 cell line and MEK S289 phosphorylation with an IC 50 =0.21 μM in Su86.86 cells in which PAK2 is downregulated [1].